Chlorinated polyvinyl chloride resin is often used in applications where its high heat deflection resistance is desired, as in hot water piping systems. However, one of its drawbacks is a high melt viscosity which makes it difficult to process as in a two roll mill, a Banbury, an extruder, an injection molder, and the like.
U.S. Pat. No. 3,360,590 to Liepins relates to chlorinated polyvinyl chloride resins which are overpolymerized with a vinyl aromatic monomer such as styrene. Improved properties are obtained such as processability, impact resistance, and tensile strength.
U.S. Pat. No. 3,923,720 to Coaker et al., relates to blends of polyvinyl chloride and various acrylate homopolymers or copolymers to improve their workability, flow, and heat distortion temperature.
U.S. Pat. No. 4,076,629 to Beaumont et al., relates to the addition of a high molecular weight aromatic hydrocarbon polymers such as polystyrene to low crystalline chlorinated polyolefins to form a sizing solution which is utilized to treat textile yarns to avoid tackiness.
U.S. Pat. No. 4,302,555 to Falk relates to blends of polyvinyl chloride and polystyrene which are compatibilized by the addition of from 1 to 20 percent by weight of a chlorinated butadiene-styrene block copolymer.